Double lock core head



Oct. 17, 1950 A. H. KENNARD DOUBLE LOCK CORE HEAD Filed March 25, 1948 Patented Oct. 17, 1950 u l-TE-DlfSTATfis. OFFICE:

Application March 23, 1943, Serial Mg, M3441 3 Claims. (01. zen-52.09)"

1. This invention relates to power transmission means for positively looking a mandrelof larger diameter than a shaft on a shaft, and in particular a plurality of locking dogs pivotally mounted between collars on a driving shaft and adapted to be inserted in the end of a mandrel holding a roll of paper.

The purpose of this invention is to provide a positive driving element that may be slid on a driving shaft and into the end of'a paper roll mandrel to'establish a positive lock between the surface of the shaft and inner surface of the mandrel. v

Locking devices'such :as clutches, set collars and the like have been used for securing paper Figure '2 is a cross'section through the power transmitting element and mandrel taken on line 22 'of Figure l. 1

Figure 3 is a longitudinal section through the device with parts shown in elevation and with the end of a mandrel shown on the device.

Figure 4 is a similar section illustrating the parts in gripping relation, and with the parts exaggerated.

Figure 5 is a similar section showing the up-' per part of the device with the upper dog in operative position wherein the driving shaft is roll mandrels on driving shafts but. particularly I in set collars it is difiicult to tighten the holdling elements when the device is in operative position, and when locking dogs are used it is difiicult to mount the dogs .so that they may be inof parallel gripping elements pivotally mounted therein with the elements positioned in gripping relation with both the surface of the driving shaft and inner surface of the mandrel.

The object of this invention is, therefore, to provide means for mounting a plurality of toothed parallel gripping dogs between collars wherein the dogs may be slid into the end of the mandrel of :a roll of paper so that they may be positioned in gripping relation with the shaft and mandrel.

Another object of the invention is to provide means for establishing positive driving relation between a shaft and a mandrel without changing the shaftor mandrel.

A further object of the invention is to provide a positive driving element adapted to be slid into the end of a mandrel of a roll of paper having a plurality of pivotally mounted gripping dogs therein which is of a simple and economical construction.

With these and other objects and advantages turning clockwise.

Referring now to the drawings wherein like reference characters denote corresponding parts the locking power transmitting element of this invention includes a .hub It), a collar ll spaced from the hub and connected thereto by ribs l2, and a plurality of gripping dogs 13 pivotally mounted on pins l4 between the hub and collar.

The hub 10 is provided with an extending sleeve l5 and an annular flange I6 is positioned around the outer end.

The dogs l3 are freely mounted between the hub and collar on the pins I4 through slightly enlarged holes I1, and the inner surface are provided with teeth 18 that contact the shaft IS. The dogs are triangulareshaped in cross section and teeth 20 and 2| are provided on the in view the invention consists of the new and outer surface that engage the inner surface 22 of a m-andril 23. v

The dogs I3 are positioned between the ribs l2 as illustrated in Figures 2 and 4, and although four dogs are shown it will be understood that as many as may be desired may be used.

With the parts arranged in this manner the element may he slid along the shaft and positioned in the end of a mandrel of a roll of paper and as the shaft is rotated the dogs will tilt slightly and the outer teeth will bite into the inner surface of the mandrel thereby forcing the mandrel with the roll of .paper to positively turn with the shaft. The transmission unit will grip when turned in either direction so that similar units may be used in both ends of the mandrel, if desired and right andleft hand units are not re- What is claimed is:

1. A locking collar comprising a plurality of parallel triangular-shaped toothed dogs, a pair of spaced collars, and means pivotally mounting the dogs in the collars with the dogs positioned between a shaft on which the collars are positioned and the inner surface of a mandrel positioned on the shaft, whereby the dogs are in gripping relation with both the shaft and mandrel.

2. A lock collar for power transmission comprising a hub, a collar spaced from the hub and connected thereto by radially disposed spaced ribs, a plurality of toothed locking dogs positioned between the hub and collar and also between the ribs,'and pins extending through the dogs with the ends thereof mounted in the hub and collar, respectively, providing pivotal mounting means for the dogs.

3. In a power transmission unit, the combination, which comprises, a hub having an extending sleeve on the outer end and also having an annular flange around the outer end, a collar spaced 4 longitudinally from the hub and connected thereto by radially disposed spaced vparallel ribs, a plurality of locking dogs, triangular shape in cross section with a shaft gripping tooth on the inner surface and with two gripping teeth on the outer surface of each dog, each of'said dogs having a longitudinally disposed bore extending from end to end thereof, and a plurality of shafts positioned through the bores of the dogs and with the ends thereof mounted in the hub and collar,

respectively.

ARCHIE H. KENNARD.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 437,125 Lewis Sept. 23, 1890 1,055,606 Cathcart Mar 11, 1913 1,560,399 Puston Nov. 3, 1925 

